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getcon(3)                  SELinux API documentation                 getcon(3)

NAME
       getcon,  getprevcon,  getpidcon  -  get  SELinux  security context of a
       process
       freecon, freeconary - free memory associated with SELinux security con-
       texts
       getpeercon - get security context of a peer socket
       setcon - set current security context of a process
SYNOPSIS
       #include <selinux/selinux.h>
       int getcon(char **context);
       int getcon_raw(char **context);
       int getprevcon(char **context);
       int getprevcon_raw(char **context);
       int getpidcon(pid_t pid, char **context);
       int getpidcon_raw(pid_t pid, char **context);
       int getpeercon(int fd, char **context);
       int getpeercon_raw(int fd, char **context);
       void freecon(char * con);
       void freeconary(char **con);
       int setcon(char * context);
       int setcon_raw(char * context);
DESCRIPTION
       getcon()  retrieves  the  context of the current process, which must be
       free'd with freecon.
       getprevcon() same as getcon but gets the context before the last exec.
       getpidcon() returns the process context for the specified PID.
       getpeercon() retrieves context of peer  socket,  and  set  *context  to
       refer to it, which must be free'd with freecon().
       freecon() frees the memory allocated for a security context.
       freeconary() frees the memory allocated for a context array.
       If con is NULL, no operation is performed.
       setcon()  sets  the  current  security  context of the process to a new
       value.  Note that use of this function requires that the entire  appli-
       cation  be  trusted  to maintain any desired separation between the old
       and new security contexts, unlike exec-based transitions performed  via
       setexeccon(3).   When  possible,  decompose  your  application  and use
       setexeccon(3) and execve(3) instead.
       Since access to file descriptors is revalidated upon  use  by  SELinux,
       the  new context must be explicitly authorized in the policy to use the
       descriptors opened by the old context if that is  desired.   Otherwise,
       attempts  by  the  process  to  use any existing descriptors (including
       stdin, stdout, and stderr) after performing the setcon() will fail.
       A multi-threaded application can perform a setcon() prior  to  creating
       any  child threads, in which case all of the child threads will inherit
       the new context.  However, prior to Linux 2.6.28, setcon()  would  fail
       if  there  are any other threads running in the same process since this
       would yield an inconsistency among the  security  contexts  of  threads
       sharing the same memory space.  Since Linux 2.6.28, setcon() is permit-
       ted for threads within a multi-threaded process  if  the  new  security
       context is bounded by the old security context, where the bounded rela-
       tion is defined through typebounds statements in the policy and guaran-
       tees  that  the new security context has a subset of the permissions of
       the old security context.
       If the process was being ptraced at the time of the setcon() operation,
       ptrace  permission  will be revalidated against the new context and the
       setcon() will fail if it is not allowed by policy.
       getcon_raw(), getprevcon_raw(), getpidcon_raw(),  getpeercon_raw()  and
       setcon_raw()  behave  identically  to their non-raw counterparts but do
       not perform context translation.
RETURN VALUE
       On error -1 is returned.  On success 0 is returned.
SEE ALSO
       selinux(8), setexeccon(3)

russell AT coker.au           21 December 2011                      getcon(3)